(Updated) Cops: On-duty fireman carrying heroin

The 24-year-old Boston fireman was allegedly caught with heroin Tuesday.

An on-duty probationary firefighter was arrested yesterday for allegedly possessing a bag of heroin.

Police said officers from the drug control unit were conducting an investigation near Columbus Avenue and Bray Street in Jamaica Plain yesterday when they saw a man walking and talking on a cell phone while carrying a plastic bag.

The officers then saw the man get into a car that drove around the block and then dropped off the man.

Police said the officers believed a drug transaction had taken place so they approached the man and allegedly found him with a plastic bag of tan powder believed to be heroin.

They then charged the man, Stephen Hogan, 24, of Dorchester, with drug possession. According to city payroll records, Hogan made $27.708 last year.

A fire department spokesman said Hogan was a probationary firefighter and was on the department for less than one year. He resigned as a firefighter Tuesday night.